Charles Dowd, a San Mateo resident and former S.F. firefighter. (Family Photo)

LINCOLN, Neb. (CBS/AP) – The family of a retired California firefighter who disappeared from an Amtrak train said it now appears that he may have fallen from the train somewhere in eastern Colorado or western Nebraska.

Charlie Dowd’s family members had been organizing searches in Omaha and Lincoln for the 69-year-old San Mateo man because they believed he may have mistakenly gotten off the train at one of those stops.

But Jen Dowd said Tuesday Amtrak police told the family a passenger on the California-to-Chicago train saw Dowd standing near a train door Thursday night. Another passenger later found an exterior door ajar around 11 p.m. Thursday.

Jen Dowd said the search for her father will now focus on the 160 miles of track between Fort Morgan, Colo., and McCook, Neb.

Dowd, a retired San Francisco firefighter, boarded the Amtrak train on Wednesday in the Bay Area. His luggage, cellphone and medication arrived in Chicago without him on Friday. Family members said they were worried that Dowd would become disoriented without his medication.

Dowd is a retired firefighter who is 5 feet 10 inches tall and weighs 175 pounds.

Anyone with any information about Charles Dowd’s whereabouts is asked to call Amtrak police at (800) 331-0008 or the Dowd family at (650) 766-6470. The family has also created a Facebook page to solicit information on Dowd’s location.

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